霍夫曼烷基化反应

苯烯比是烷基化反应中重要的调节参数,其值直接影响产品的质量与收率。从原理上分析了高苯烯比的必要性,并经生产实践将苯烯比定为8:1。在此基础上,根据影响苯烯比的主要因素,对生产工艺进行了改造,将实际苯烯比调整到合适值。改造达到了工业生产要求,取得了较好的经济效益。

Shape selective alkylation of polynuclear aromatics has begun to receive increasing attention. 2,6 dialkylnaphthalenes are important raw materials for manufacturing high quality polyester fibers and plastics. Understanding of the reaction and the catalysis for conversion of polycyclic aromatic hydrocarbons is needed both from fundamental and practical view points. In this paper, alkylation of naphthalene with propene over a series of dealuminated mordenite with different Si/Al ratios was carried out in an autoclave with an electromagnetical stirrer. Textural property of the dealuminated mordenite was determined by nitrogen adsorption. The amount of the acid sites was measured by NH 3 TPD. The catalytic activity of HM and β shape selectivity for products increased with increasing the Si/Al ratio in HM. Moreover, the selectivity for alkylation with propene was also increased by dealumination treatment. The increase of the catalytic activity was attributed to the formation of mesopores, which significantly promoted the diffusion of reactants and products in mordenite. It was suggested that the increase of β selectivity resulted from the elimination of acid sites from the external surface, and the selectivity for alkylation with propene was improved owing to the creation of the interconnection between 12 ring and 8 rimg channels by dealumination.